<!DOCTYPE html>
<html lang="zh_CN">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <style>
        .box{

            position: relative;
            position: absolute;
            position: fixed;

        }
    </style>
</head>
<body>
    <div class="box">
        <div class="son"></div>
    </div>
</body>
<script type="text/javascript">

</script>

</html>
